In general, a compressor is a mechanical apparatus compressing gas by means of a rotating motion of an impeller or rotor or a reciprocating motion of a piston. Such compressors are divided into a reciprocating compressor, a rotary compressor and a vane type compressor according to compressing methods.
Normally, in a scroll compressor which is a kind of rotary compressor, a fixed scroll and an orbiting scroll are installed at upper and lower portions inside a hermetic container. The fixed scroll is fixed to the hermetic container, and the orbiting scroll is installed to be eccentrically rotatable with respect to the fixed scroll by a driving unit. Here, involute laps formed respectively on the fixed scroll and the orbiting scroll are engaged with each other to define a compression chamber compressing refrigerant. Since a space between the hermetic container and the orbiting scroll is filled with refrigerant to be sucked into the compression chamber, it maintains a low pressure state. On the contrary, since a space between the hermetic container and the fixed scroll is filled with refrigerant compressed in the compression chamber, it maintains a high pressure state.
FIG. 1 is a view illustrating an example of a fixed scroll of a conventional scroll compressor. As illustrated in FIG. 1, in the conventional fixed scroll 1, involute laps 1a defining a compression chamber P are formed at a lower portion of a disk, and a discharge hole 1b bored like a straight line is provided in a central blocked portion of the disk. Accordingly, when an orbiting scroll (not shown) is eccentrically rotated with respect to the fixed scroll 1, refrigerant is sucked into the compression chamber P between the fixed scroll 1 and the orbiting scroll, compressed, and discharged through the discharge hole 1b of the fixed scroll 1.
The conventional scroll compressor has a disadvantage in that, since the discharge hole of the fixed scroll is formed like a straight line, pulsation noise of refrigerant excessively occurs. Even if a separate muffler is added to suppress the pulsation noise of refrigerant, component addition and mounting processing complicates a production process and increases a production cost.